Surface enhanced Raman scattering is being applied to the problem of trace detection and monitoring of explosives. Results have shown tremendous potential of colloidal gold particles on which the intensity of TNT Raman bands was found to be enhanced by 105. A practical detection scheme is being developed by using self-assembled monolayers of gold particles on a solid substrate. Several metal colloidal films have been prepared and characterized. Enhanced Raman scattering for TNT adsorbed on colloidal gold films has been demonstrated.